Light Emitting Diodes (LEDs) are semiconductor devices that convert electricity into infrared light or the like using properties of compound semiconductors to enable transmission/reception of signals, or that are used as light sources.
Group III-V nitride semiconductors are in the spotlight as core materials of light emitting devices, such as LEDs or Laser Diodes (LDs), due to physical and chemical properties thereof.
Such LEDs do not contain environmentally harmful materials, such as mercury (Hg), used in conventional lighting apparatuses, such as incandescent bulbs, fluorescent lamps, etc., and are eco-friendly and, moreover, have several advantages including low power consumption, semi-permanent lifespan and the like. As such, conventional light sources are being rapidly replaced with LEDs.
FIGS. 1A and 1B are plan views showing conventional light emitting devices.
The conventional light emitting device as exemplarily shown in FIG. 1A consists of an n-type semiconductor layer 10, active areas 20, p-type bumps 30-1, 30-2 and 30-3 and an n-type bump 40. The conventional light emitting device as exemplarily shown in FIG. 1B consists of an n-type semiconductor layer 10, active areas 22, p-type bumps 30-1 to 30-5 and n-type bumps 40-1 to 40-4.
Referring to FIGS. 1A and 1B, in these conventional light emitting devices, the active areas 20 or 22 are disposed in contact with each other rather than being spaced apart from each other. In this case, overlapping portions 50 to 60 of the active areas 20 or 22 exhibit deteriorated heat radiation.